Scored-cylinder repair.



H ORACE J. YGUNT, OF ZNDIANAPOLIS, INDIANA.

'SCDRED-CYLINDER REPAIR.

Specification of Letters Patent. Patmr'tetl Feel), 2?, hill? Application filed may 22, 1916. Serial Ho. 99,192.

To all whom is may concern:

Be it known that I, Home J. focus, a citizen of the Unzted States, res1d1ng at In dinnapolis, in the county of Marion and State of Indiana, have invented certain new and useful mprovei'nents in Scorsd-Cylin der Repair, of which the following is a specification. In internal combustion engines for automobiles, boats and the like, the connecting rods are attached to the pistons by the medium of a piston pin which is secured in an eye at the end of the connecting rod. This pin, from carelessness and other causes, very "frequently becomes loose and working endwise by use contacts with the inner wall of the cylinder and wears grooves or scores in it causing leakage past the piston which the pack 1g rings cannot close. This scoring of the interior of the cylinder is often developed on two of its diametrically opposite sides by reason of the loose pin shifting often and contacting with the cylinder at its alternate opposite ends. Automobiles as now constructed each commonly have from :tour to twelve cylinders which proportionately increases the chances of trouble from. scoring, and these cylinders are generally cast in integral groups which would necessitate the discarding of the group to displace a scored cylinder with a new one.

Various expedients have been resorted to for repairing scored cylinders, the one meeting with the most favor being to weld in metal strips to fill the scores; but this. involves the heating oi. the cylinder to so high a temperature that it becomes warped, requiring it to be bored out to a greater than the original diameter. Besides the labor involved this necessitates the discarding of the ol piston for a larger one and the changes in size throw this part of the engine out of time with the rest.

The object of my invention is to repair a scored cylinder and make it as good as new without heating it or enlarging its bore, and to accomplish this at such a satisfactory saving in cost over the expense of a new one as will make the repair of scored cylinders alwaysworth while.

. Referring tothe accompanying drawing which is illustrative of my invention Figure 1 is a longitudinal central section of a scored cylinder before it has been re paired, and Fig. 2 is a perspective view on a larger scale of a scored cylinder after it has been repaired in accordance with my in vention.

In Fig. 1, the cylinder 3, pistonl, connecting rod 5 attached to the piston by pin 6 (which isgenerally hollow), shaft 7 and crank 8, are of usual and well known 'construction, and the piston is shown with a pair of parallel scores 9, formed by the contact of the end of pin 6.

In the exercise of my invention these scores or grooves, if they are not toowide, are individually widened at their inner or bottom portions by the aid of a planing machine or otherwise, to form channels whichare dovetail in cross section, or iii the sur facebetween the scores is so damaged as to need entire renewal Inialre a single channel of suilicient width to embrace both score lines, the purpose being always to remove all of the broken and damaged interior surface of the cylinder. In all cases the channel is formed with longitudinal inwardly beveled edges.

In the channel thus formed 1 fit a. strip of metal, preferably copper, which more rapidly when heated than does the csst iron from which the cylinder is cash This metal strip is thicker than the depth of the channel. endwise through the outer end of the chair nel and is made to fit as closely as possible for easy driving insertion. It is then thor oughly expanded by hammering-or rolling along its entire exposed surface until every portion of the channel is filled and it is as tight as it can be made in this way. Then the projecting portions of the hammered copper are removed and it isrnade to conform by careful scraping to the curved surface of the inner bore of the cylinder.

This completes the operation. The pair of narrow parallel copper strips 10 are easier to finishto the interior surface of the cylin der than is the wider strip 10 but in all cases I have found by experience that the repair is perfect in operation and is durable. The copper being inserted and finished cold will additionally tighten when the cylinder becomes heated inause because its-expansibility from heat is greater than that of the iron with whichit is associated.

I do not desire to be limited to the use of copper, as its alloys as Welles other metals will give satisfactory results, nor do I desire to limit my invention to a channel the shape of which is dovetail in cross section, but

It is inserted by slipping in roca-tes, said cylinder having channels with undercut sides in its inner wall surface and metal filling sald channels, said metal having greater relative expansibility than the metal of the cylinder, and said metal can.- forming in outside shape With the bore of the cylinder. 4

In Witness whereof, I have hereunto sel; my hand and seal at Indianapolis, Indiana, this 12th day of May, A. D. one thousand nine hundred and sixteen.

HORACE J. YOUNT. [13.3.] 

